Aspartame degradation reaction

The rate of aspartame degradation in dry mixes is more dependent on the water activity than on the temperature (23). In dry mixes, aspartame may also engage ia Maillard reactions with the aldehyde moieties of flavoting agents, resulting ia the loss of sweetness and flavor. Use of the corresponding acetals of the flavor compounds to avoid this reaction has been reported (24). 

Bell, L.N. and Hageman, M J. 1994. Differentiating between the effects of water activity and glass transition dependent mobility on a solid state chemical reaction Aspartame degradation. J. Agric. 

Bell et al. (2002) investigated the relationship between water mobility as measured by oxygen-17 NMR (transverse relaxation rate obtained from linewidth at half-height) and chemical stability in glassy and rubbery polyvinylpyrrolidone (PVP) systems. Reported results suggest that water mobility in PVP model systems was not related to Tg. The study did not find a link between water mobility and reaction kinetics data (half-lives) for degradation of aspartame, loss of thiamin and glycine, and stability of invertase. 

Aspartame and its degradation products aspartylphenylalanine, aspartic acid, and phenylalanine can also be separated after reaction with naphthalene-2,3-dicarboxaldehyde (NDA) in the presence of cyanide (sodium or potassium cyanide) in borate buffer (50 mM, pH 8). This reaction affords highly fluorescent and stable l-cyano-2-substituted-benz[/]isoindole (CBI) derivatives that can be detected at 420 nm excitation and 490 nm emission. The CBI derivatives are separated on a TSK ODS-120T column using a gradient of 30-80% B (acetonitrile water, 9 1 v/v) in A (50 mM acetate buffer, pH 6.0) (75). 

Waters pBondapak Cl 8 3.9 x 300 mm MeOH 15% NaH2P04 0.5M, ph adjusted to 2.1 with H3PO4, 85% Separates aspartame from 6 degradation products 2.0 for first 15.1 min, then 3.0 from 15.1 to 20 min Aqueous acidic reaction solutions (Int. std., tyrosine) 200 nm 25... 

Aspartame is the most widely used artificial sweetener in the world. It was approved by the FDA for use in the USA in 1981, and now is approved for use in several other countries of the world. One of the drawbacks of aspartame is its instability to heat and acid. Under acidic conditions aspartame slowly hydrolyzes leading to a loss of sweetness, chemical interaction, and microbial degradation. The shelf life of the aspartame-sweetened products with high water content is limited to about 6 months, after which it breaks down into its constituent components and loses its sweetening abilities. At elevated temperatures, solid aspartame slowly releases methanol to form aspartyl phenylalamine and the dioxopiperazine. This reaction is especially favored at neutral and alkaline pH values. Because of this reason, aspartame cannot be used in hot baking foods. 

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